Question

The following terms are used in this standard.

Statement coverage — whether a statement has been executed or not, where statement is anything defined as a statement in the LRM. Covered means it executed at least once. Some implementations also permit querying the execution count. The granularity of statement coverage can be per-statement or per-statement block (however defined).

FSM coverage — the number of states in a finite state machine (FSM) that this simulation reached. This standard does not require FSM automatic extraction, but a standard mechanism to force specific extraction is available via pragmas.

Toggle coverage — for each bit of every signal (wire and register), whether that bit has both a 0 value and a 1 value. Full coverage means both are seen; otherwise, some implementations can query for partial coverage. Some implementations also permit querying the toggle count of each bit.

Assertion coverage — for each assertion, whether it has had at least one success. Implementations permit querying for further details, such as attempt counts, success counts, failure counts and failure coverage.

These terms define the “primitives” for each coverage type. Over instances or blocks, the coverage number is merely the sum of all contained primitives in that instance or block.